We present a re-evaluation of the taxonomic status of Agave gypsophila, for which a narrower circumscription is proposed, and four new species from western Mexico are described and illustrated: Agave abisaii, A. andreae, A. kristenii and A. pablocarrilloi. All four species are narrow endemics occurring on a variety of limestone outcrops and belong to the subgenus Agave and to the Marmoratae species group sensu Berger. They are morphologically related to A. gypsophila s. s. from Guerrero, Mexico, but clearly differ from it in various qualitative and quantitative morphological and ecological characteristics.